Heating device



ALBERT A. RADTKE, OF CHICAGO, ILLINOIS.

HEATING DEVICE Specification of Letters Patent.

Patented. Sept. 10, 1907.

Application filed October 27,1906. Serial No. 340,797.

To all whom it may concern: Be it known that I, ALBERT A. RADTKE, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Heating Devices, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification My invention relates to electrical heating devices, itsv object being to provide aheating receptacle in which the heating mediunr can be brought into uniform proximity to the object to be affected by the heat.

The device which I shall describe as an illustration of my invention is an egg cooking device, so arranged that the electrical conductors from which the heat emanates are so disposed in the receptacle that an egg inserted therein will be heated uniformly, thus preventing bursting of. the egg which would take place if the heat were not applied uniformly. Where the device is to be used for cooking eggs, the interior of the receptacle is more or less egg-shaped and is lined with electrical resistance conductors, and the egg may come into direct contact with these conductors. The

A switch 12 is suitably mounted on the standard or block 3, and the other terminal of the conductor 10 connects with one terminal of this switch. The other terminal of the switch connects with the strand 13 of a flexible cord, the other strand 14; of which connects with the lower terminal of the winding 4 in the base part. When the ends of theflexible cord are connected with a supply circuit and the switch 12 turned on, current will flow serially through the windings 4 and 5, the resistance .of these windings being adjusted to provide for any desired heating'thereof. Instead of having the terminals 6 and 7 in direct contact, a dowel pin arrangement might also be used. Any other arrangements for providing electrical contact between the upper and lower windings will readily suggest themselves. The standard or block 3 is provided with suitable channels or passageways 15 for receiving the various conductors passing therethrough.

The base and cover parts or shells 1 and 2 are preferably of material which is a non-conductor to heat, such as asbestos, dielite or other substance, but I prefer to use dielite, as thi's'can be readily cast when in liquid form. Various means may be employed for forming receptacle is preferably in two parts, a base part and cover part, the egg being dropped into the base part and the cover part applied, suitable provision being made to electrically connect together the conductors in both parts and also with a source of current supply. Where the device is to be used for heating other objects, the shape thereof can be made accordingly.

In the accompanying drawing I have illustrated a device of simple construction which may be used for cooking eggs.

Figure 1 is an exterior view of the device, and Fig. 2 is a vertical, diametrical, sectional view thereof.

The receptacle itself, as a whole, is egg-shaped, as shown, and consists of the lower base portion 1 and the upper or cap part 2. The base part 1 is mounted on a block or standard 3. The electrical conductors 4 in the base part and 5 in the cap part are preferably wound spirally to entirely line the interior of these 1 parts. The upper terminal (3 of the conductor in the base part may extend along the upper edge of the base part, as shown, to be electrically engaged by the lower end 7 of the conductor in the cap part. A metallic dowel pin 8 is shown embedded in the edge of the cap part opposite the terminals 6 and 7 and connects with the upper terminal of the conductor 5 in the cap part. In the edge of the cap part is an opening or hole 9 for receiving the dowel pin when the cap is placed in position, and a conductor 10 is shown as terminating in a contact end 11 in the bottom of the hole 9 to be engaged by the dowel pin 8 when the cover is put in place, thus connecting the conductor 10 with the conductor in the the winding structure. One way of doing this would be to wind the conductors over a former of wax having the shape which it is desired to give to the interior of the receptacle. This former with the windings thereon is then placed in a mold and the liquid dielite poured around it.

The parts I and 2 may primarily be cast integral and then separated, or these parts may be cast separately in the first place. After the dielite has solidified, the wax core is removed, and the windings will be permanently embedded in the walls of the shells, and the various connecting conductors can also be embedded in the shells, as shown. The dowel pins may then be inserted, the contacts suitably arranged, and the base part I mounted in the block 3, the conductors being then suitably connected with the flexible cord and with the switch. The wire forming the windings may be insulated and the various turns then arranged adjacent to each other, or bare wire may be used and the turns separated sufficiently to allow entrance of the liquid dielite between them which dielite then forms an insulating medium between the turns.

When an egg is placed in the base and the cover" put in place, the heat emanating from the wires upon passage of current therethrough will be sufficiently uniformly distributed to the egg to .cause cooking thereof without bursting of the shell. Eggs can be baked or boiled by placing them in an oven, but bursting usually results owing to the ununiform application of heat to the egg, the egg usually being heated too rapidly where it comes in contact with the bottom or cap part.

, side of the oven. Eggs, therefore, are usually boiled in Water which insures the uniform distribution of heat. Water, however, can be raised to a temperature of only 212 degrees; consequently, the time required to boil an egg cannot be brought below a fixed mini- 5 mum, usually about three minutes for soft boiling and five or more minutes for hard boiling. By means of my device, the temperature can be raised to any degree and the time for soft boiling or hard boiling decreased correspondingly, and as the heat is uniformly applied, there is no danger of bursting. The egg also being intimately surrounded by the windings which are themselves surrounded by shells of material nonconductive to heat, the heat from the windings is confined and concentrated on the egg. Instead of leaving the wires bare, they may be lined with a thin shell of dielite or other material. mainly lor the purpose of protecting the wires against abrasion or moisture which might result in short circuits.

A device of this constructimr could also be used for baking potatoes. for instance. or other vegetables. or for uniformly heating similarly shaped objects. A plurality of these outfits might also be grouped on a common standard block and the windings either singly controlled by switches or in common by a main switch. 2 It can be readily seen that a device or devices of this kind will be of great. utility, as great saving in labor and time is effected by their use. I do not wish to be limited to the exact construction and arrangement I have here shown nor to the modifications to which I have referred. the broad feature of the invention being the arrangement of windings and protection therefor for heat to be concentrated uniformly on the object to be treated.

I claim as new and desire to secure by Letters Patent: 1. In an electrical egg cooking device. the combination of an inclosing shell comprising a base and a cap portion. and electrical conductors arranged within the base and cap portions to form a lining therefor. the interior contour of the receptacle being such that the windings will be brought. into uniform and intimate proximity to the egg placed within the receptacle to be heated.

2. In an electrical egg cooking device. the combination of an inclosing casing or shell comprising a base part and a cover or cap part. electrical conductors arranged to line the interior of the base part. electrical conductors arranged to line the interior of the cap part. and means for affording electrical connection between the windings in the.

base and cap parts when these parts are brought together. the contour of the interior of the shell being such that the windings are in uniform and intimate proximity to the egg within the shell to be heated.

3. In an electrical heating device, the combination of an inclosing shell comprising a base portion and a cap or cover portion therefor, a mounting block in which the base portion is mounted, windings arranged within the base and cap portions and adapted for connection with a source of current supply, and a switch forming part of the device for controlling the connection of the windings with the current source, the interior contour of the device being such that the windings will be in uniform proximity to an object placed within the shell to be heated.

4. In an electrical heating deyice, the combination of an elliptical inclosing shell formed of material non-conductive to beat. said shell comprising a base portion and a cap portion fitting thereon, electrical conductors arranged within the base and cap portions to form a lining therefor, and suitably arranged terminals for connecting together the windings in the cap and base portions when these portiuns are brought together, said shell being entirely inclosed when the cover and base parts are brought together and the interior contour being such that the windings will be in substantially uniform proximity to the object to be heated.

In an egg" heating or cooking device, the combination of an elliptical inclosing shell for entirely inclosing the egg. electrical conductors lining the interior of the casing and disposed to apply heat uniformly to the egg when connected witlra source of current supply to cook the egg by induction.

6. in an egg heating device, the combination of electrical conductors wound to form an egg-shaped shell for intimately receiving and surrounding the egg, :1 protecting and supporting shell surrounding the windings, and means for controlling the connection of said windings with a source of current supply, the protecting shell being of material which is nonconductive to heat.

7. In an electrical cooking device, the combination of an int-losing casing. and windings arranged within the interior of the casing adapted for connection with a source of current supply, said wires being arranged to intimately receive the object to be cooked, thereby to cause uniform heating thereof.

In an electrical cooking device. the combination of an inclosing casing. and wires lining the interior of the casing adapted for connection with a source of current supply. said wires being arranged to intimately receive the object to be heated to heat said object by conduction, said easing being of material which is a non-conductor of heat whereby the heat generated by the windings is concentrated on the object to be heated.

In witness whereof. I hereunto subscribe my name this 23th day of October. A. I'). 1906.

ALBERT A. RAD'IKE.

Witnesses (.IIAllLI-lS .T. SCHMIDT. Gnoum: E. IIIGIIAM. 

